Fix literal promotion

src/common.cpp

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright (c) 2015-2025 Advanced Micro Devices, Inc. All rights reserved.
+ * Copyright (c) 2015-2026 Advanced Micro Devices, Inc. All rights reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -195,6 +195,21 @@
     else
     {
         auto common = common_shape(to_shapes(inputs));
+        if(options.common_type)
+        {
+            std::vector<shape> tensor_shapes;
+            for(const auto& input : inputs)
+            {
+                if(not(input->can_eval() and input->get_shape().elements() == 1))
+                    tensor_shapes.push_back(input->get_shape());
+            }
+            if(not tensor_shapes.empty())
+            {
+                auto tensor_type = compute_common_types(tensor_shapes);
+                if(tensor_type != common.type())
+                    common = shape{tensor_type, common.lens()};
+            }
+        }
         std::transform(inputs.begin(), inputs.end(), inputs.begin(), [&](auto input) {
             if(options.common_lens and input->get_shape().lens() != common.lens())
             {

src/onnx/parse_gru.cpp

@@ -1,7 +1,7 @@
 /*
  * The MIT License (MIT)
  *
- * Copyright (c) 2015-2025 Advanced Micro Devices, Inc. All rights reserved.
+ * Copyright (c) 2015-2026 Advanced Micro Devices, Inc. All rights reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -61,7 +61,7 @@
 {
     std::vector<op_desc> operators() const { return {{"GRU"}}; }
 
     std::vector<instruction_ref> parse(const op_desc& /*opd*/,
                                        const onnx_parser& parser,
                                        onnx_parser::node_info info,
                                        std::vector<instruction_ref> args) const
@@ -166,7 +166,12 @@
         {
             gru_transpose_inputs(info, args);
         }
-
+        if(not args[5]->is_undefined() and
+           args[5]->get_shape().type() != args[1]->get_shape().type())
+        {
+            args[5] = info.add_instruction(
+                make_op("convert", {{"target_type", args[1]->get_shape().type()}}), args[5]);
+        }
         // first output for concatenation of hidden states
         auto hidden_states =
             info.add_instruction(make_op("gru",

test/common_test.cpp

@@ -0,0 +1,85 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015-2026 Advanced Micro Devices, Inc. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "test.hpp"
+#include <migraphx/common.hpp>
+#include <migraphx/module.hpp>
+#include <migraphx/make_op.hpp>
+#include <migraphx/literal.hpp>
+#include <migraphx/instruction.hpp>
+
+TEST_CASE(add_common_op_scalar_literal_preserves_tensor_type)
+{
+    migraphx::module mm;
+
+    auto tensor = mm.add_parameter("x", migraphx::shape{migraphx::shape::half_type, {1, 100, 128}});
+    auto scalar =
+        mm.add_literal(migraphx::literal{migraphx::shape{migraphx::shape::float_type}, {1e-5f}});
+
+    auto result = migraphx::add_common_op(mm, migraphx::make_op("add"), {tensor, scalar});
+
+    EXPECT(result->get_shape().type() == migraphx::shape::half_type);
+}
+
+TEST_CASE(add_common_op_scalar_literal_preserves_tensor_type_reversed)
+{
+    migraphx::module mm;
+
+    auto tensor = mm.add_parameter("x", migraphx::shape{migraphx::shape::half_type, {1, 100, 128}});
+    auto scalar =
+        mm.add_literal(migraphx::literal{migraphx::shape{migraphx::shape::float_type}, {1e-5f}});
+
+    auto result = migraphx::add_common_op(mm, migraphx::make_op("add"), {scalar, tensor});
+
+    EXPECT(result->get_shape().type() == migraphx::shape::half_type);
+}
+
+TEST_CASE(add_common_op_two_tensors_promotes_to_wider_type)
+{
+    migraphx::module mm;
+
+    auto half_tensor = mm.add_parameter("x", migraphx::shape{migraphx::shape::half_type, {1, 128}});
+    auto float_tensor =
+        mm.add_parameter("y", migraphx::shape{migraphx::shape::float_type, {1, 128}});
+
+    auto result =
+        migraphx::add_common_op(mm, migraphx::make_op("add"), {half_tensor, float_tensor});
+
+    EXPECT(result->get_shape().type() == migraphx::shape::float_type);
+}
+
+TEST_CASE(add_common_op_float_tensor_with_float_scalar_keeps_float)
+{
+    migraphx::module mm;
+
+    auto tensor =
+        mm.add_parameter("x", migraphx::shape{migraphx::shape::float_type, {1, 100, 128}});
+    auto scalar =
+        mm.add_literal(migraphx::literal{migraphx::shape{migraphx::shape::float_type}, {1e-5f}});
+
+    auto result = migraphx::add_common_op(mm, migraphx::make_op("add"), {tensor, scalar});
+
+    EXPECT(result->get_shape().type() == migraphx::shape::float_type);
+}
+
+int main(int argc, const char* argv[]) { test::run(argc, argv); }